Cita APA

National Geographic Society (U.S.). (1991). National Geographic picture atlas of our world. The National Geographic Society.

Citación estilo Chicago

National Geographic Society (U.S.). National Geographic Picture Atlas of Our World. Washington D.C: The National Geographic Society, 1991.

Cita MLA

National Geographic Society (U.S.). National Geographic Picture Atlas of Our World. The National Geographic Society, 1991.